Reactivation of human herpesvirus type 6 in multiple organ failure syndrome

Human herpesvirus type 6 (HHV-6) and cytomegalovirus (CMV) are known to int eract with the production of cytokines. In this study, we sought to determi ne the incidence of HHV-6 and CMV reactivation during multiple organ failur e syndrome (MOFS) and to evaluate the potential effects of viral replicatio n on both the morbidity and mortality associated with MOFS. Viral reactivat ion was assessed by use of specific polymerase chain reaction (PCR) analysi s of the serum samples obtained from 48 consecutive patients with MOFS (the MOFS group) and from 48 sex- and age-matched patients with <2 organ failur es (the control group). In addition, HHV-6 replication was assessed in 106 blood donors (the normal group). The incidence of HHV-6 replication was hig her in the MOFS group than in the control and normal groups (26 [54%] of 48 vs. 7 [15%] of 48 and 5 [5%] of 106, respectively; P <.0001), with apparen tly no influence on morbidity and mortality rates. In contrast, reactivatio n of CMV was found in a single patient. Further studies are needed to evalu ate the pathogenesis of HHV-6 replication in critically ill patients.